1. Field of the Invention
This invention relates to an apparatus for recording and reproducing information on and from a recording medium. This invention also relates to a recording medium. This invention further relates to a head positioning apparatus for an information recording and reproducing system.
2. Description of the Prior Art
Japanese published unexamined patent applications 56-163536, 57-6446, 57-212642, and 60-70543 disclose a recording medium having both a magnetic recording portion and an optical recording portion.
Japanese published unexamined patent application 2-179951 discloses a recording medium which has an optical recording portion and a magnetic recording portion at opposite sides thereof respectively. Japanese patent application 2-179951 also discloses an apparatus which includes an optical head facing the optical recording portion of the recording medium for reading out information from the optical recording portion, a magnetic head facing the magnetic recording portion of the recording medium for recording and reproducing information into and from the magnetic recording portion, and a mechanism for moving at least one of the optical head and the magnetic head in accordance with rotation of the recording medium. In the apparatus of Japanese patent application 2-179951, during the processing of the information read out from the magnetic recording portion, a decision is made as to whether or not the information recorded on the optical recording portion is necessary, and a step of reading out the information from the optical recording portion is executed when the information on the optical recording portion is decided to be necessary.